US2421470A - Honing device - Google Patents

Description

June 3,1947. www 2,421,470

HON ING DEVICE Filed Aug. 20, 1943 FIGS.

Q INVENTOR.

JOSEPH SUNNEN ATTORNEY.

F IG.I6.

Patented June 3, 1947 UNITED STATES PATENT OFFICE 9 Claims.

This invention relates to honing devices and more particularly to a new and improved mandrel and hone assembly capable of securing maximum accuracy in the finish of the holes and also for the purpose of maintaining evenly balanced pressures on the operating surfaces of the hohes.

I have found that the greatest accuracy in 1inish can be obtained by the use of a hone arbor havingl two circumferentially spaced hones and a guide, so that the hone arbor assembly has a three point contact with the interior surface of the hole which is being finished.

It might be assumed that with such construction, the two hones and the guide might be spaced at equal intervals of 120 around the circumference as the pressure on each of the hone surfaces would be exactly equal while the hone is stationary in the hole. However, I have found that the hones do not wear evenly as might be eX- pected from an analysis of the forces when the hone is not actually rotating in the work.

I have discovered a method of spacing and locating the hones and the guide in such a manner as to substantially equalize the cutting action of the hones while also obtaining a substantial increase in the accuracy of the finished work.

An object of my invention is to provide a new and. improved hone arbor capable of finishing the inside surfaces of holes with greater accuracy than has previously been obtainable.

It is a further object of my invention to produce a new and improved hone varbor assembly which is capable of performing the cutting operation at a maximum rate without sacrifice of accuracy.

It is a further object of my invention to produce a new and improved hone arbor assembly of the type having two circumferentially spaced hcnes and a guide in which the hohes are equally loaded per unit area during operation.

It is a further object of my invention to produce a new and improved hone arbor assembly of the type having two circtunferentially spaced bones and a guide in which the rate of wear of the two hones will be substantially uniform.

The invention will be better understood uponV reference to the following description and accompanying drawings, referring to which:

Figure 1 is an end view of a hone arbor assembly embodying my invention.

Figure 2 is a side elevation of the hone arbor shown in Figure 1.

Figure 3 is a sectional view of the hone arbor shown in Figure 1, taken along the section line 3--3 of Figure 1.

Figure 4 is a sectional view of the arbor taken along section line 4-4 of Figure 3.

Figure 5 is a side elevation of one of the wedge retainer members. This figure is drawn to twice the scale used in the preceding figures.

Figure 6 is an end View of the guide and retainer members shown in Figure 5.

Figure 7 is a plan view of the guide and retainer members shown in Figures 5 and 6.

Figure 8 is a side elevation of the hone shown in Figures 1, 2 and 3, the figure being drawn to twice the scale of said figures.

Figure 9 is a plan view of the hone shown in Figure 8.

Figure 10 is an end view of the hone shown in Figures 8 and 9,

Figure 11 is an inverted plan view of th shown in Figures 8, 9 and 10.

Figure l2 is a side elevation of one of the wedge retainers shown in Figures 2 and 3 looking from the rear with respect to Figure 3, drawn to a scale twice that of Figure 3. Y

Figure 13 is an inverted plan view of the device shown in Figure 12.

Figure 14 is a plan view of the device shown in Figures 12 and 13.

Figure 15 is an inverted side elevation of the wedge member, drawn to twice the scale used in Figures 1, 2 and 3.

Figure 16 is a plan view of the wedge member shown in Figure 15.

The reference numeral I indicates a honefarbor suitable for use in any honing machine and particularly adaptable for use in connection witha machine such as shown in my Patent No. 2,070,381. The arbor is provided with a shank 2 having retaining means 3 adapted to lit into and be driven by the spindle of the honing machine. The spindle (not shown) carries a longitudinally slidable member 4 for operating the adjusting cam, and this member extends into a bore 5 in the shank of the arbor, having a coupling member 5 to engage a corresponding coupling mem.- ber 'I carried by the plug 8 which is slidable in the bore 5. The arbor is provided with longitudinal slots 9 to receive the lugs I0 which are attached to the member 8 by suitable screws I I in such a manner as to permit longitudinal adjustment by movement of the member 4. The arbor is provided with longitudinal grooves I2 and I3 to receive the hones I4 and the slidable wedge members l5.

The wedges I5 are provided with notches I6 to snugly fit over the lugs I0, so that longitudinal movement of the lugs will result in a correspondhone ing movement of the wedges. The hones are provided with projecting cam members I'I and I 8 which are eccentrically spaced with respect to the center of the hone and mounted parallel with each other to cooperate with cam grooves I9 and 20 formed in the wedges I5. The hones and wedges, together, snugly ll the lateral width of the grooves I2 and I3.

The wedges are held against radial movement by the hooksZI on the retainers 22 and 23, while the hone is permitted to move radially as the wedges are adjusted. This radial movement of the hone is permitted by the coupler slots 24 formed at the ends of the hones to engage corresponding coupler slots 25 on the member` 22. While only a single hone in each groove is shown, two or more hones can be coupled together in the same groove by means of the coupling slots, it being understood that additional cam grooves corresponding to the grooves I9 and 20 in the member I will' be provided where additional hones are to be used.

The hone comprises a metallic support member`|4 having an abrasive stick 26 rigidly secured to the upper edge thereof. The construction and arrangement' will be fully understood from Figures 8 to 1l, inclusive, and it is more fully describedand claimedin my copending application Serial No. 427,654, filed January 21, 1942.

Member 23 is held in position in the grooves I 2 andl I3- by screws extending into the holes 2S, suitable holes 29 being formed in the shaft for this purpose. Corresponding screw holes 39 in the member 22 receive screws which are inserted through the holes 3| in the arbor. The member 23 is provided with a recess 32 having a-central projection 33 to which is attached a flat spring 34 coiled around the central projection and extending outwardly so as to Contact the coupler at the end'of the hone. It will be understood that the coupler'may extend into the recess and hook into the wall 35 thereof, so that the spring 34 will retain the hone against longitudinal movement with respect to the arbor, if desired.

.Athird longitudinal groove 35 is formed in the arbor and constructed and arranged to carry one ornioresuitable guide members 31. These guide members may be formed of metal, plastic, or any material having the desired degree of hardness `andco-eiiic'ient of friction for the purposes hereinafter to be described. The guide members are heldin position by screws 38, the heads of which extend into slots 39 formed in the arbor at the side of the groove`36 as shown in Figure 1. These screws'are threaded into the guide members, so that when the screws are tightened, they extend beyond the wall thereof against the opposite wall of the groove as indicated in Figure 1. As the guide wears, it may be raised by inserting oneor more shims IIB between the bottom of the groove andthe guide.

The angular spacing of the grooves I2, I3 and 35E with respect to each other and the direction o'f rotation is an important feature of this invention. The direction of rotation of the arbor is counterclockwise with respect to Figure 1 as indicated by the arrow. In order to secure even pressures on the abrasive sticks 26 and 26| operating in the grooves I2 and I3, respectively, the relative co-eicients of friction of the guide 31 and of the abrasive sticks with the material which is being worked on must be taken into consideration. Ordinarily, the guide has a much lower co-efiicient of'friction than the hones, especilally when the grain of the abrasive material is coarse or when the material being worked on is soft.

In order to secure maximum speed in the removal of metal in the honing operation, it is necessary to have both hones operating at the maximum cutting rarte they will stand without causing excessive wear. In order to secure this result, the hones must be equally loaded; that is, the pressure with which they are held outwardly against the inside of the hole must be kept equal. This equality of pressure would be obtained by spacing the hones and the guides at when the hone is stationary, but I have found that a different condition is set up when the hone is in operation.

In operation, the turning action of the hone in the work sets up a moment arm about each contact surface as an axis, and the magnitude of the torque is a function of the outward pressure applied to the hones by the cams, multiplied by a function of the co-eflicient of'friction of the surface ofthe guide or hone with the material which is Ibeing worked on, and divided by the length of the arm represented Iby the spacing of the trailing contact surface. This results in the loading of each contact surface by the friction of the sliding surface which precedes it. For instance, in Figure 1, the friction of the hone in the groove I2 increases the load of the hone in the groove I3, while the hone in the groove I3 loads the guide 31 which, in turn, loads the hone in the groove I2. As long las the co-efiicient of friction of the guide is lower than that of the hones, the hone l2 will be loaded substantially less than the hone in the groove I3.

I have foundy that the disadvantages due to uneven loading of the hones can be substantially eliminated by spacing the hones |at unequal intervals in such a manner that the moment arm from the leading hone 26 tol the trailing hone 26| is increased, while the resultant of the initial load on the hones 25|- and-3'I is directed more nearly parallel to the center line of the hone 26 than the resultant of the initial load on hone 26 and cam 31 is to the centerline of the hone 25|.

Obviously, the spacing of the hones and guides in accordance with this principle should theoretically vary with the relative co-eiiicients of friction of the guide and hone members, and these, in turn, will depend on the coarseness of the hone being used, as well as on other factors. However, I have found that a workable arrangement which is adaptable to most conditions is substantially that shown in the drawings in which the leading hone follows the guide by approximately and the trailing hone follows the leading hone by approximately leaving 85 between the trailing hone and the guide. It will be understood that the principles, apparatus, and method described herein may be embodied in various ways and that the angles mentioned are merely by way of illustration and are not intended as limitations.

I claim:

1. In a hone arbor assembly, an arbor having a pair of longitudinal grooves therein, said grooves being circumferentially spaced at an angle greater than 120 and less than 180, hones in said grooves, and non-abrasive guide means carried by said hone arbor at a point angularly spaced from and opposed to said hones in such a position as to balance the working loads applied to the hones in operation.

2. In a hone arbor assembly, an arbor having a pair of longitudinal grooves therein, said grooves being circumferentially spaced at an angle greater than 120 and less than 180, hones in said grooves, said arbor being constructed and arranged to normally rotate in one direction, and non-abrasive guide means carried by said hone arbor at a point angularly spaced from and opposed to said hones, said guide means being substantially more distantly spaced from the groove which it follows than from the groove which it precedes in rotation whereby the working loads applied to the hones in operation are balanced.

3. In a hone arbor assembly, a hone arbor, a pair of circumferentially spaced longitudinal grooves in said arbor, similar hones in said grooves, each hone comprising a hone support and an abrasive stick, said hone supports having cam surfaces on a, side adjacent the center of the grooves, wedges mounted in said grooves at the side of said hone supports, said wedges having cam surfaces cooperating with the cam surfaces on the respective hones, said wedges being longitudinally slidable in said grooves for the purpose of adjusting said hone, and guide means for adjusting said wedges.

4. In a hone arbor assembly, a hone arbor, a pair of circumferentially spaced longitudinal grooves in said arbor, similar hones in said grooves, each hone comprising a, hone support and an abrasive stick, said hone supports having cam surfaces on a side adjacent the center of the grooves, wedges mounted in said grooves at the side of said hone supports, said Wedges having cam surfaces cooperating with the cam surfaces on the respective hones, said wedges being longitudinally slidable in said grooves for the purpose of adjusting said hone, guide means for adjusting said wedges, and guide means carried by said arbor at a point-l opposed to said hones.

5. In a hone arbor assembly, a hone arbor, a pair of circumferentially spaced longitudinal grooves in lsaid arbor, similar hones in said grooves, each hone comprising a hone support and an abrasive stick, said hone supports having cam surfaces on a side adjacent the center of the grooves, wedges mounted in each of said grooves at the side of said hone supports, said wedges having cam surfaces cooperating with the cam surfaces on the respective hones, said wedges being longitudinally sildable in said grooves for the purpose of adjusting said hone, a single adjusting member carried by said arbor, and means connecting said adjusting member with both of said wedges for simultaneous adjustment thereof.

6. In a hone arbor assembly, a hone arbor, a pair of circumferentially spaced longitudinal grooves in said arbor, similar hones in said grooves, each hone comprising a hone support and an abrasive stick, said hone supports having cam surfaces on a side adjacent the center of the grooves, wedges mounted in each of said grooves at the side of said hone supports, said wedges having cam surfaces cooperating with the cam surfaces on the respective hones, said wedges being longitudinally slidable in said grooves for the purpose of adjusting said hone, a single adjusting member carried by said arbor, and means connecting said adjusting member with both of said wedges for simultaneous adjustment thereof, said hones being spaced circumferentially from each other at an angle greater than and less than and a single bearing member circumferentially spaced from and opposed to said hones at unequal angles.

7. In a hone arbor assembly, a hone arbor, a pair of circumferentially spaced longitudinal grooves in said arbor, similar hones in said grooves, each hone comprising a hone support and an abrasive stick, said hone supports having cam surfaces on a side adjacent the center of the grooves, wedges mounted in said grooves at the side of said hone supports, said wedges having cam surfaces cooperating with the cam surfaces on the respective hones, said wedges being longi tudinally slidable in said grooves for the purpose of adjusting said hones, control means for adjusting said wedges, said hones being spaced circumferentially from each other at an angle greater than 120 and less than 180, and guide means carried by said arbor at a point opposed to said hones, said guide means being eccentrically spaced with respect to said hones.

8. In a hone arbor, a pair of circumferentially spaced hones located on one side of a plane containing the axis of the arbor, and a non-abrasive guide located on the other side of said plane, said guide and said hones being similarly positioned with respect to the axis of said arbor so that their working surfaces would rotate in the same cylindrical path.

9.- In a hone arbor, a pair of circumferentially spaced hones located on one side of a plane containing the axis of the arbor, and a non-abrasive guide located on the other side of said plane, said guide and said hones being similarly positioned with respect to the axis of said arbor so that their working surfaces would rotate in the same cylindrical path, the angular position of said hones being differentially spaced with respect to said guide.

JOSEPH SUNNEN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,195,055 Wallace Mar. 26, 1940 2,309,485 Wallace Jan. 26, 1943 1,989,831 Sunnen Feb. 5, 1935 FOREIGN PATENTS Number Country Date 36,972 Netherlands Dec. 16, 1935

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